A rostral denticle of Ischyrhiza mia, a species belonging to an extinct group of sawfishes that lived in North American waters during the late Cretaceous period, around 100 to 65 million years ago.

Sawshark (Pristiophorus spp.)Sawsharks are a genus of deep-sea sharks known for their long, saw-like snouts, which they use to detect and capture prey. Several species within this genus are rare ...